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Home , Brown recluse spider, Heteropoda venatoria, Huntsman spider

EENY299

Brown Recluse , Loxosceles reclusa Gertsch & Mulaik (Arachnida: Araneae: )1 G. B. Edwards2

Introduction I called the Florida Poison Control Network to confirm these numbers, and was cited 182 total cases and 96 in the The brown ,Loxosceles reclusa Gertsch & Tampa region. The actual numbers are less important than Mulaik, is frequently reported in Florida as a cause of the fact that a significant number of unconfirmed brown necrotic lesions in humans. For example, in the year 2000 recluse spider bites are reported in the state every year. Yet alone, Loft (2001) reported that the Florida Poison Control not one specimen of has ever been Network had recorded nearly 300 alleged cases of brown collected in Tampa, and the only records of Loxosceles recluse bites in the state; a subset of 95 of these bites was species in the entire region are from Orlando and vicinity. reported in the 21 counties (essentially Central Florida) A general review of the brown recluse, along with a critical under the jurisdiction of the regional poison control center examination of the known distribution of brown recluse in Tampa. and related in Florida, seems in order at this time. Distribution Loxosceles reclusa was described by Gertsch and Mulaik (1940) from . At the time of the first revision of the genus Loxosceles in the (Gertsch 1958), the known distribution ranged from Central Texas to southern , east through middle to western Tennessee and northern Alabama, and south to southern Mississippi. Gorham (1968) added , , and northern . Later, he added , , and , with scattered introductions in other states, includ- ing Florida; his map indicated a record in the vicinity of Tallahassee (Gorham 1970).

Weems and Whitcomb (1975) noted that, “on many oc- Figure 1. Female brown recluse spider, Loxosceles reclusa Gertsch & casions specimens have been inadvertently brought into Mulaik. Florida in trucks and automobiles, hidden in luggage, Credits: Jeffrey Lotz, Division of Plant Industry

1. This document is EENY299, (originally published as DPI Entomology Circular 406), one of a series of the Entomology and Nematology Department, UF/IFAS Extension. Original publication date August 2003. Revised August 2015. Visit the EDIS website at http://edis.ifas.ufl.edu. This document is also available on the Featured Creatures website at http://entnemdept.ifas.ufl.edu/creatures/.

2. G. B. Edwards, Florida Department of Agriculture and Consumer Services, Division of Plant Industry; UF/IFAS Extension, Gainesville, FL 32611.

The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other UF/IFAS Extension publications, contact your county’s UF/IFAS Extension office. U.S. Department of Agriculture, UF/IFAS Extension Service, University of Florida, IFAS, Florida A & M University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension. boxes, and various commercial cargoes, but to date it In summary, the verified records of brown recluse and appears to have been unsuccessful in establishing breeding related spiders in the state are limited to the following eight populations in Florida.” It is unfortunate that they did not out of 67 Florida counties: Alachua, Bay (Callaway), Dade document these alleged records, as this comment is not (Lemon City), Duval (Jacksonville), Jefferson (Monticello), completely in accord with the following reference. Leon (Tallahassee), Orange (Orlando), and Osceola (Runnymede). The more northern counties (Alachua, Bay, An updated revision of the genus by Gertsch and Ennik Duval, Jefferson, and Leon) were all isolated records of the (1983) reported a few records from Arizona, California, native brown recluse, Loxosceles reclusa, whereas the more , Florida, Maine, Minnesota, New Jersey, New southern county records (Dade, Orange, and Osceola) were Mexico, New York, North Carolina, Wyoming, and of the introduced Mediterranean recluse, Loxosceles rufes- Tamaulipas (Mexico) the reported Ontario (Canada) record cens. The Alachua, Dade, and Jefferson county records were in this publication subsequently proved to be a specimen interceptions of single specimens. The Bay, Duval, Leon, of Loxosceles rufescens (Dufour); R. Vetter, personal Orange, and Osceola county records were infestations in communication, 2001. Most of these peripheral records one or two buildings. There is no evidence to support either were interceptions of one or two specimens, not evidence the notion that a widespread population of brown recluse of established populations. The Florida records consisted spiders exists in Florida or that there are numerous intro- of two specimens, one each from Alachua (collected 10 ductions of brown recluse into the state. Therefore, there January 1969) and Jefferson (Monticello, collected 21 is no reason to assume that frequent interactions between August 1968) counties, and both were taken from inside brown recluse and humans occur in Florida. Subsequent to automobiles. Subsequently, a sailor was bitten on the hand the original publication of this work (as a DPI Entomology by a male brown recluse in the cargo hold of a naval ship Circular), Loxosceles rufescens was found in a warehouse in in Jacksonville, in March 1986. This ship had just arrived Escambia County, Florida; and Loxosceles laeta (Nicolet), from North Carolina, where it had loaded supplies. To the , was found in a home in Polk date, this appears to be the only verified case (the actual County, Florida (Edwards 2002a). causative agent of a bite captured and identified) of brown recluse in Florida [due to complicating factors, I have personally identified several hundred Florida spiders medical personnel familiar with this case even questioned submitted for identification by the public, and only one the veracity of this one alleged bite]. specimen (the Bay County record) proved to be a brown recluse spider. In addition, I have seen thousands of Florida Within the last two years, single buildings (in Callaway, spiders submitted by professional biologists and inspectors, Jacksonville and Tallahassee) have been found to contain with only the few specimens mentioned above proving to populations of Loxosceles reclusa (Edwards 1999, 2000, be members of the genus Loxosceles. It appears obvious to 2001). There is reason to believe that all three of these re- me that the chance of interaction between brown recluse cords are the result of movement of infested materials from spiders and people in Florida is close to nil, agreeing with other states, so it is entirely possible that the infestations are Vetter’s (2000) assessment of reported brown recluse bites restricted to these buildings and can be eliminated. Such outside the natural range of the spider. Medical personnel was the case with an infestation of the similar Loxosceles should, therefore, consider a multitude of more likely rufescens found in Orange County (DPI records from causes (see below) before diagnosing and treating a necrotic Orlando: 28 January 1982, 4 January 1983 and 18 August wound as a brown recluse bite. 1986) in a single building; the spiders were subsequently eradicated. Description The only other records ofLoxosceles rufescens occurring The description is taken from Gertsch (1958). Adults of in Florida are a few juvenile spiders in buildings in both sexes are similar in appearance and size, ranging from nearby Osceola County (Runnymede; Banks 1904) and about 7 to 12 mm in body length. Adult females average one juvenile specimen from Dade County (Lemon City; slightly larger, about 9 mm compared to about 8 mm for Gertsch 1958). This cosmopolitan species is probably native adult males. The carapace is pale yellow to reddish brown, to the Mediterranean region, and is sometimes called the with a dusky brown patch just in front of the median groove Mediterranean brown spider or Mediterranean recluse. It (which is encompassed by a narrow, dark line); this patch is has been recorded from a number of localities across the united to the front of the carapace by dusky brown stripes. U.S., particularly in larger cities, where it is transported by In total, these markings appear in the form of a violin. In commerce (Gertsch and Ennik 1983). addition, three dusky patches occur along the margin

Brown Recluse Spider, Loxosceles reclusa Gertsch and Mulaik (Arachnida: Araneae: Sicariidae) 2 on each side. The sternum is yellowish, with other ventral the brown recluse (Edwards 1983). The male palp length body parts of the cephalothorax darker reddish brown. of Loxosceles reclusa is under 4 mm, considerably less than the superficially similar crevice spider. Another difference between the two species is that Loxosceles reclusa has six eyes composed of three isolated pairs (dyads), whereas Kukulcania hibernalis has eight eyes all clumped together in the middle front of the carapace.

Figure 2. Detail of the carapace of the brown recluse spider, Loxosceles reclusa Gertsch & Mulaik, showing the dark fiddle-shaped marking often used to identify this spider. Credits: James L. Castner, University of Florida

The legs are slender and dusky orange to dark reddish brown. They are numbered front to back with Roman numerals (I, II, III, IV). In females, the leg length formula, Figure 4. Male , Kukulcania hibernalis (Hentz). longest to shortest, is II, IV, I, III, typically with leg II being Credits: Jeffrey Lotz, Division of Plant Industry over 18 mm in length, and leg III about 15 mm, the other two pair intermediate in length. The male leg formula is II, I, IV, III, with leg II over 24 mm and leg III about 17 mm. The abdomen of both sexes is tan to brown, but it may appear darker if the spider has recently fed. Juveniles are paler in all respects, as are occasional adults.

Figure 5. The three pairs of eyes that help identify the brown recluse spider, Loxosceles reclusa Gertsch & Mulaik. Credits: Jim Kalisch, University of Nebraska - Lincoln

The only other Florida spiders with an eye arrangement similar to Loxosceles are the spitting spiders of the genus Figure 3. Adult brown recluse spider, Loxosceles reclusa Gertsch & Mulaik, showing leg length relative to a US quarter. Scytodes, but these spiders have a domed carapace, lack Credits: Jim Kalisch, University of Nebraska - Lincoln a violin-shaped carapace marking, and are not known to cause serious wounds in humans. Occasionally, the hunts- Males of the common southern house spider, Kukulcania (= man spider, venatoria (Linnaeus), is misidenti- Filistata) hibernalis (Hentz), are frequently confused with fied as a brown recluse (Edwards 1979). However, the color

Brown Recluse Spider, Loxosceles reclusa Gertsch and Mulaik (Arachnida: Araneae: Sicariidae) 3 pattern on the carapace of this species is reversed, with a among stored papers, in the corrugations of cardboard light median mark on a dark background, and adults of this boxes, and in discarded articles, such as tires, inner tubes, spider are much larger than a brown recluse. and assorted other junk. Most of the specimens found in feral conditions were under rocks, especially in bluff outcrops, with a few under bark or in logs. They definitely seemed to prefer dry conditions.

Spiderlings appear to stay with their mother for three to four instars before dispersing. They feed on prey provided by the mother during this time. Once dispersed, they may establish a home territory, where they stay through several more instars, as evidenced by the presence of several successive molts. Spiders go through a total of eight instars. Irregular webbing is seen in the nest area. Prey consists of a variety of other , including rather dangerous prey like other spiders and ants. The attack consists of a sudden lunge and bite, usually on an intended prey’s ap- pendage, after which the brown recluse immediately backs away (personal observation). The acts rapidly to Figure 6. Female , Scytodes sp. paralyze the prey, preventing any retaliation for the initial Credits: G.B. Edwards, DPI attack of the recluse spider. After the prey is overcome by the venom, the brown recluse moves in to feed. Relatively harmless prey, particularly mobile prey like houseflies, will be held with the initial bite and not released.

Figure 7. Male , (Linnaeus). Credits: Jeffrey Lotz, DPI

Biology Hite et al. (1966) made the earliest thorough report of the Figure 8. Female brown recluse spider, Loxosceles reclusa Gertsch & Mulaik, with egg sac. biology of Loxosceles reclusa. In their study, they recorded Credits: Jeffrey Lotz, Division of Plant Industry the habitat of 626 brown recluse in found from May 1962 to December 1964. Most (430) were found in Most mating and reproduction occurs during June and July. buildings and outbuildings, especially in boxes and among Females were frequently found with more than one egg sac. papers, in every room from basement to attic. They were In the laboratory, females made up to five egg sacs. Total found in almost any place which had remained undisturbed eggs per female ranged from 31 to 300, total hatched young for lengthy periods of time, such as behind pictures, maximized at 158 for a single female; the largest number of beneath or behind furniture, in boxes of toys, in clothing, young from one egg sac was 91; and percent emergence of

Brown Recluse Spider, Loxosceles reclusa Gertsch and Mulaik (Arachnida: Araneae: Sicariidae) 4 young was 0 to 100. Some eggs were fed on by spiderlings will then turn black as cells die. Eventually the necrotic core from previous egg sacs still in the web, or even by the falls away, leaving a deep pit that gradually fills with female (perhaps these were infertile). The egg stage aver- tissue. aged about 13 days, instars I-VIII 17, 110, 63, 41, 38, 34, 40, and 53 days respectively. Maximum age for a brown recluse Experimental antivenin (Rees et al. 1981; not commercially from emergence to death was 894 days for a female, 796 for available) was very successful when administered within a male. A laboratory-kept specimen lived over six months 24 hours, but many times a victim does not seek treatment without food or water. Captive specimens also proved until after is well underway (more than 24 hours), moderately resistant to pesticides. These two characteristics after which the antivenin is less effective. Systemic effects illustrate why brown recluse populations may exist in usually take two to three days to show symptoms. Bites that buildings for long periods of time, despite repeated efforts become systemic usually do not also become necrotic; it to eradicate them. is thought that in necrotic wounds the venom is localized in the tissue whereas in systemic reactions the venom is Bites and Bite Symptoms distributed quickly into the body without necrotic local ef- fects. The wound is usually free of bacterial infection for the Brown recluse spiders usually bite only when they become first two to three days but may be contaminated by patients trapped next to the victim’s . Bites occur either when due to pruritis (itching) leading to scratching. Recluse sleeping humans roll onto the spider or put on clothes venom can exhibit extended necrosis in adipose (fatty) into which the spider has crawled (Vetter and Visscher tissue of thighs, buttocks and abdomen of obese patients; 1998). Typically bites occur under clothing, mostly on the there is also a gravitational flow of the venom effects, at thigh, upper arm, or lateral torso, less often on the neck times leading to satellite pockets of necrosis. Healing can (Anderson 1998) [Dr. Philip C. Anderson is a physician and take weeks to months and may leave an unsightly scar, medical researcher who has worked on brown recluse bites although scarring is minimal in most cases. Skin grafts and venom for 40 years]. may be required to complete healing in the worst cases, but should be considered a last resort. Description of the symptoms is from Wingo (1960), Gorham (1968, 1970), Anderson (1982, 1998), and Vetter and Visscher (1998). Reactions to a bite vary from no Medical Analysis noteworthy symptoms to severe necrosis or systemic The following technical analysis is condensed from the effects. Discomfort may be felt immediately after the bite, or medical literature. People who suspect they have been several hours may pass before any local reaction to the bite victimized by a brown recluse spider bite are strongly occurs. In one study, only 57% of the patients realized they encouraged to consult with a physician. had been bitten at the time of the bite. It must be realized that there are at least two significant variables affecting In medical terms (Vetter 1998), bites from Loxosceles can the outcome of a bite. The first is the amount of venom be unremarkable (requiring no care), localized (requiring injected by the spider. Like some venomous snakes, spiders some care but usually healing without intervention), are known to sometimes give “dry” bites, with little or no dermonecrotic (a slow- healing, necrotic ulcerated lesion venom injected. The second variable is the sensitivity of the needing supportive care), or systemic (vascular and renal victim. Some people are simply more prone to have a severe damage, sometimes life-threatening). Within 10 minutes reaction in instances where another person might only have of venom injection, there is a constriction of capillaries a slight reaction. around the site of the bite. A major venom component is sphingomyelinase D which causes (destruction Typical symptoms are as follows. Symptoms start two to six of red blood cells). Recluse venom has a strong disruptive hours after the bite. Blisters frequently appear at the bite effect on endothelial tissue. Polymorphonucleocytes (PMN) site, accompanied by severe pain and pronounced swelling. are activated (by the patient’s immune system) and infiltrate A common expression is the formation of a reddish blister, the bite site; in test where PMN activity was sup- surrounded by a bluish area, with a narrow whitish separa- pressed, degree of necrosis was lessened. General symptoms tion between the red and blue, giving a “bull’s-eye” pattern. are edema (swelling), erythema (redness caused by blood By 12 to 24 hours, it is usually apparent if a Loxosceles being brought to the surface to counteract the damage), wound is going to become necrotic because it turns purple pruritis (itching), pain at the site, and mild fever. A pruritic in color; if necrotic symptoms do not express by 48 to 96 or painful eruption can occur within a few hours of the bite hours, then they will not develop. If the skin turns purple, it and persist for a week, ending with scaling and peeling of

Brown Recluse Spider, Loxosceles reclusa Gertsch and Mulaik (Arachnida: Araneae: Sicariidae) 5 the hands, and a truncal papular rash, which recalls pictures Alternatives to Consider in of scarlet fever rashes; the pruritis may be worse for the patient than the painful focal necrosis. The skin may feel Suspected Cases of Brown Recluse hot and tender to the patient. It may be advisable to treat Bite the rash and pruritis symptoms with prednisone (Anderson Spider bites cause clean infarctions in the skin. If an inflam- 1998). Treatment with corticosteroids does not appear to matory core lesion exists, necrotizing infection should be affect either the skin necrosis or the hemolysis (Anderson anticipated, not spider bite. A number of other arthropods 1998). and an assortment of diseases, some caused by microorgan- Dermatologic expression varies. In mild self-healing isms and some with other causes, are known to produce wounds, the bite site may not progress past an edematous necrotic or apparent pre-necrotic wounds. Vetter (1998) erythema; these wounds do not become necrotic and gives a list of causative agents of necrotic wounds (related non-intrusive care is sufficient. In more serious wounds, a discussion can be found at the associated website). This list sinking blue-gray macule on the skin contains a “bull’s- eye” includes most of the following conditions: pattern formation where a central erythematous bleb Tick-induced: tick bites and tick-borne diseases, such as (blister) is separated from a peripheral cyanotic region erythema chronicum migrans () and Rocky by a white zone of induration (red-white-blue). If the bite Mountain Spotted Fever; becomes violaceous within the first few hours, this usually indicates that severe necrosis may occur and more sup- Viral: chronic herpes simplex, infected herpes simplex, portive measures are necessary. herpes zoster (shingles); The initial bleb gives way to ischemia (localized temporary Bacterial: Gonococcal (G.C.) arthritis dermatitis, Myco- blood deficiency). A central eschar (hardened scab similar bacterium ulcerans, infection, to that made after burns) forms, hardens, and within seven infection; to 14 days the eschar falls out leaving behind an ulcerated depression. The necrosis may continue to spread from Fungal: keratin cell mediated response to a fungus, the bite site possibly due to an autoimmune response sporotrichosis; (see above). Normally, the wound limits begin to recede after one week as healing begins. Unnecessary removal Blood Disorders: focal vasiculitis, purpura fulminans, of tissue often leads to greater scarring than would result thromboembolic phenomena; from normal healing. Extirpation of damaged skin is only recommended in severe cases and only after the limits of Underlying Disease States: diabetic , chronic liver the wound are strongly demarcated at six to eight weeks. disease (spontaneous necrotizing fasciitis), pyoderma gan- Most wounds self-heal with excellent results. grenosum, toxic epidermal necrolysis (Lyells syndrome);

Systemic conditions that might manifest in severe cases Cancer: leukemia, lymphomatoid papulosis (LyP), are hematoglobinuria (hemoglobin in the urine), hema- lymphoma; toglobinemia (reduction of useful hemoglobin, resulting in anemia-like condition), (reduction Reaction to Drugs/: alcoholism, erythema nodosum, of clotting platelets in the blood), and/or disseminated warfarin and poisoning; intravascular coagulation (DIC) (precipitation of platelets causing mini-clots all over the body). The presence of Topical: chemical burn (e.g., oven cleaner), poison ivy/oak sustained coagulopathy with hemolysis indicates severe infection; systemic . Fortunately, less than 1% of cases exhibit these symptoms. Although rare, if death occurs, it is Miscellaneous/ Multiple Causative: bed sores, erythema most often from hemolysis, renal failure and DIC; children multiforme, Stevens-Johnson syndrome, self-inflicted are most adversely affected due to their small body mass. wounds; Anderson (1998) noted, however, that none of the fatalities were proven to have been caused by a brown recluse spider. Unknown Causative Agents: periarteritis nodosa. Other possibilities include subcutaneous blisters and hives caused by stings of hymenopterous insects (ants, bees,

Brown Recluse Spider, Loxosceles reclusa Gertsch and Mulaik (Arachnida: Araneae: Sicariidae) 6 yellowjackets, wasps), welts from urticating caterpillars, Dame DA, Fasulo TR. (2002). Venomous Arthropods. bites by predatory or parasitic bugs (assassin bugs, bed Public Health Pesticide Applicator Training Manual. http:// bugs), and other parasitic insect bites (black flies, mos- entomology.ifas.ufl.edu/fasulo/vector/chapter_07.htm(10 quitoes, horse and deer flies, fleas). It is even possible that August 2015). some as yet untested native spider is the cause of serious Dominquez TJ. 2004. It’s not a spider bite, it’s community- necrotic wounds. For example, circumstancial evidence acquired methicillin-resistant Staphylococcus aureus. in one case implicated Ctenus captiosus Gertsch (Edwards Journal of the American Board of Family Practice 17: 1989), a wandering spider, as a cause of a necrotic bite, 220-226. although a recent assay of the venom of this species did not find sphingomyelinase D (Dr. G. J. Bodner, personal Edwards GB. 1979. The giant spider,Heteropoda communication, 2001). venatoria (Linnaeus) (Araneae: Sparassidae). Florida De- partment of Agriculture and Consumer Services (FDACS), The expression ofLyme disease can give the classic Division of Plant Industry, Entomology Circular 205 1-2. “bull’s-eye” patterning characteristic of brown recluse bite. Edwards GB. 1983. The southern house spider,Filistata Although Lyme disease is rare in Florida, it does exist and hibernalis Hentz (Araneae: Filistatidae). FDACS, Division would be a more probable diagnosis than brown recluse of Plant Industry, Entomology Circular 255: 1-2. bite. Misdiagnosis in this case could be serious since Lyme Edwards GB. 1989. The Florida false , Ctenus disease can be treated and cured with common antibiot- captiosus (Araneae: Ctenidae). FDACS, Division of Plant ics. If diagnosed as “brown recluse bite” instead, it will Industry, Entomology Circular 319: 1-2. obviously be treated as such; the Lyme disease then may progress to serious symptoms of heart and central nervous Edwards GB. 1999. Insects of Medical and Veterinary system disorders, and can result in death. In treating alleged Importance, In Halbert SE. (editor). FDACS, Division of spider bite victims, a question that medical personnel Plant Industry, Tri-Ology (Entomology Section) 38: 8. should be asking is whether the patient has recently Edwards GB. 2000. Insects of Medical and Veterinary traveled outside the area where they live. They should also Importance, In Halbert, S.E., ed., FDACS, Division of Plant attempt to be aware of potentially embarrassing etiological Industry, Tri-Ology (Entomology Section) 39: 8. agents such as filthy lifestyle habits (squalid conditions that might encourage vermin such as bed bugs) or unhygienic Edwards GB. 2001. Insects of Medical and Veterinary use of drug paraphernalia (Vetter 1998). Importance, In Halbert, S.E., ed., FDACS, Division of Plant Industry, Tri-Ology (Entomology Section) 40: 8. Postscript Edwards GB. (2002a). Chilean recluse, Loxosceles laeta (Nicolet) (Araneae: Sicariidae) in Florida. Pest Alert. Anderson (1982) made perhaps the most appropriate com- http://www.freshfromflorida.com/Divisions-Offices/ ment concerning spider bites, “In general, spiders attempt Plant-Industry/Plant-Industry-Publications/Pest-Alerts/ to avoid people. People should accommodate them.” Pest-Alerts-Chilean-Recluse (10 August 2015). Edwards GB. (2002b). Venomous Spiders in Florida. Pest Acknowledgments Alert. http://www.freshfromflorida.com/pi/enpp/ento/ Dr. D. Sollee, Florida Poison Control Network, provided venomousspiders.html (10 August 2015). statistics on brown recluse bites in Florida. R. Vetter, Uni- Gertsch WJ. 1958. The spider genusLoxosceles in North versity of California, Riverside, reviewed the manuscript America, Central America, and the West Indies. American and contributed valuable discussions about brown recluse Museum Novitates 1907: 1-46. distribution and bites. Gertsch WJ, Ennik F. 1983. The spider genusLoxosceles Selected References in North America, Central America, and the West Indies (Araneae, Loxoscelidae). Bulletin, American Museum of Anderson PC. 1982. Necrotizing spider bites. American Natural History 175: 265-360. Family Practitioner 26: 198-203. Gertsch WJ, Mulaik S. 1940. The spiders of Texas. I. Bul- Anderson PC. 1998. Missouri brown recluse spider: a letin, American Museum of Natural History 77: 307-340. review and update. Missouri Medicine 95: 318-322. Gorham JR. 1968. The brown recluse spiderLoxosceles Banks N. 1904. The Arachnida of Florida. Proceedings, reclusa and necrotic spider bite - A new public health Academy of Natural Science, Philadelphia 56: 120-147.

Brown Recluse Spider, Loxosceles reclusa Gertsch and Mulaik (Arachnida: Araneae: Sicariidae) 7 problem in the United States. Journal of Environmental Health 31, 8 pp. Gorham JR. 1970. The brown recluse. United States Depart- ment of Health, Education, and Welfare, Public Health Service Publication 2062. Hite JM., Gladney WJ, Lancaster JL Jr., Whitcomb WH. 1966. Biology of the brown recluse spider. University of Arkansas, Agricultural Experiment Station Bulletin 711: 1-26. Loft K. 2001. DO NOT DISTURB. BayLife, Tampa Tribune, May 22, 2001. Rees R, Shack RB, Withers E, et al. 1981. Management of brown recluse spider bite. Plastic Reconstructive 68: 768-773. Vetter RS. (2003). Causes of necrotic wounds other than brown recluse spider bites. University of California, Riv- erside, Entomology Insect Information, Spiders and other . http://spiders.ucr.edu/necrotic.html (10 August 2015). Vetter RS. 2000. Myth: idiopathic wounds are often due to brown recluse or other spider bites throughout the United States. Western Journal of Medicine 173: 357-358. Vetter RS, Edwards GB, James LF. 2004. Reports of enven- omation by brown recluse spiders (Araneae: Sicariidae) outnumber verifications ofLoxosceles spiders in Florida. Journal of Medical Entomology 41: 593-597. Vetter RS, Visscher PK. 1998. Bites and stings of medically important venomous arthropods. International Journal of Dermatology 37: 481-496. Weems HV Jr., Whitcomb WH. 1975. The brown recluse spider, Loxosceles reclusa Gertsch and Mulaik (Araneae: Loxoscelidae). FDACS, Division of Plant Industry, Ento- mology Circular 158 : 1-2. Wingo CW. 1960. Poisonous spiders. University of Mis- souri, Agricultural Experiment Station Bulletin 738: 1-11.

Brown Recluse Spider, Loxosceles reclusa Gertsch and Mulaik (Arachnida: Araneae: Sicariidae) 8